A 1-V Diode-Based Temperature Sensor with a Resolution FoM of 3.1pJ•K2 in 55nm CMOS

BJT-based CMOS temperature sensors are widely used thanks to their high accuracy and low calibration cost. However, they usually require an over-1V supply voltage [1], [2], and their accuracy degrades in advanced CMOS processes [3]. Recently, capacitively-biased ‘diode’ (CBD) designs [4], [5] were proposed to be compatible with a sub-1V supply voltage. However, such designs still have limited energy efficiency (>20pJ•K2) [4] and poor relative inaccuracy (>1%) [4], [5]. This paper presents a 1-V CBD temperature sensor, where the CBD is embedded into a switched-capacitor (SC) $\sum \Delta$-ADC, thereby improving both the sensor’s energy efficiency and accuracy.